stroke Flashcards
how would an anterior cerebral artery stroke present?
contralateral hemiparesis + sensory loss
LOWER extremity > upper extremity
how would a middle cerebral artery stroke present?
contralateral hemiparesis + sensory loss
UPPER > lower extremity
contralateral homonymous hemianopia
aphasia - speech probs
how would a posterior cerebral artery stroke present visually?
contralateral homonymous hemianopia with macula sparing
visual agnosia - can’t recognise/identify objects
how would a posterior inferior cerebellar artery stroke present?
lateral medullary syndrome/Wallenberg syndrome
ipsilateral - facial pain + temp loss
contralateral - limb/torso pain + temp loss
ataxia, nystagmus
how would an anterior inferior cerebellar artery stroke present?
similar to posterior inferior (Wallenburgs)
+ ipsilateral facial paralysis + deafness
how would a basilar artery stroke present?
“locked-in” syndrome
characterised by quadriplegia and bulbar palsy
Cognition and eye movements are preserved in many patients
how would a stroke affecting basal ganglia, thalamus or internal capsule present?
lacunar stroke
either isolated hemiparesis, hemisensory loss or hemiparesis with limb ataxia
strong assoc with hypertension
best prognosis of all strokes
define a TIA
<24hrs of symptoms with complete resolution however 50% of these episodes will show damage on MRI, ischaemia without infarction
True TIA last less than an hour – usually 10-15mins
Any residual symptoms suggests stroke not TIA
what can cause the disruption in blood supply in stroke?
thrombus/embolus - patients with AF
atherosclerosis
shocl
vasculitis
drugs - heroin, cocaine
haem problems - antiphopholipid, leukamia
infection - HIV, meningitis
septal defects
total anterior circulation syndrome (TACS)
hemiplegia involving at least 2 of face, arm, and leg +/- hemisensory loss contralateral to the lesion
homonymous hemianopia
cortical signs - dysphasia, neglects
occurs in 20% of infarcts
most severe type of stroke with only bput 5% of patients being alive + independent at 1 year
Watershed areas
(areas between 2 arterial territories) sensitive to hypoxia
Some brain regions more sensitive (e.g. neocortex and hippocampus
how long post stroke/TIA can you drive a car and lorry?
car = 4wks
lorry =1yr
what are those with haemorrhagic stroke more likely to have?
decrease level of consciousness in 50%
headache
N+V
seizures in 25%
risk factors for haemorrhagic stroke
elevated systolic BP overweight
- High fasting glucose
- High cholesterol
- Alcohol, smoking
- Atrial fibrillation – 1 in 6 strokes due to AF
stroke scoring systems
Rosier - score >0 stroke is likely
FABS - >3 suggests stroke mimic
modified rankin scale - used to look at outcomes
NIHSS - severity scale
ABCD2 - early risk of stroke/TIA
CT differences between ischaemic + haemorrhagic
Ischaemic
- Areas of low density in grey + white matter of territory
- Hyperdense artery corresponding with responsible arterial clot
Haemorrhagic
Areas of hyperdense material blood surrounded by low density oedema
FAST
public health campaign, recognize stroke symptoms
o Face – has fallen on one side, can they smile?
o Arms – can they raise both arms + keep them there?
o Speech – is there speech slurred?
o Time – time to call 999 if you see any of these
management of strokes
CT to determine ischaemic or haemorragic
thrombectomy
offer asap + within 6hrs of symptom onset
together with thrombolysis (if no contraindications
if confirmed occlusion to proximal anterior circulation shown by angiography
thrombolysis
if no contraindiactions (lots)
within 4.5hrs of onset of stroke symptoms
-> thrombolyse with IV alteplase (IV tPA)
aspirin 300mg asap after stroke, wait 24hrs if been thrombolysed
contraindications to thrombolysis
on anticoagulant
previous haemorrhage or untreated anneurysm
pregnancy/postpartum
recent surgery
severe co-morbidities - liver disease/malignancy
seizure
recent stroke
recent head injury
low platelets (<100)
severe hypertension - can be treated first
lowering BP pre thrombolysis
Only indicated in 2 scenarios (acutely)
* For safe thrombolysis
* ICH as attempt to reduce haematoma expansion
options
* IV labetalol, IV GTN
management of mild stroke
NIHSS <=3
give aspirin + clopidogrel for up to 3 weeks
management of haemorrhagic stroke
Most not suitable for surgical intervention
STOP
- anticoagulants – warfarin
- antithrombotic – clopidogrel
Reverse – vit K/prothrombin complex for warfarin
Lower bp
complications of strokes
lots but
malignant MCA syndrome
post stroke pneumonia
hypertensive encephalopathy
malignant MCA syndrome
- Rare syndrome seen in very large anterior territory stroke
- Occurs 2-5days post stroke, can be <24hrs
- Problematic in young
- 80% mortality
- Treatment = hemicraniotomy
May be left with significant disability
post stroke pneumonia
- In 15% of patients, commonly occurs within first week
- Due to immunosuppression secondary to stroke + dysphasia
- Dysphasia management – swallow screen
o If abnormal, assessment by speech + language
o May need NG tube, thickened fluids etc
hypertensive encephalopathy
- Severely hypertensive
- Symptoms of raised ICP
Pathological finding - Global cerebral oedema
- Tentorial + tonsillar herniation
- Arteriolar fibrinoid necrosis
- petechiae
strokes on CT
haemorrhage appears bright
infarct may not show immediately - often see resultant oedema (dark area)
may see blocked artery - hyperdense MCA sign
